Speaking of netflix app say I'm watching a movie and want to go back to the main netflix menu how can I do that without exiting the whole netflix app? Is that possible? Thanks sorry if it's stupid question

It changes depending on the Netflix release and your TiVo hardware (eg, TiVoHD vs Roamio). "Up" works for some setups, "Zoom" works for some, "Back" (a new button on Roamio remotes) is the newest possibility.